1. Field of the Invention
This invention relates to systems and methods of accessing diverse databases, directories, Web Services and applications with a published API (application programming interface) via a common access layer.
2. Description of the Related Art
It is well known in computer science that tables and their relationships in a relational database have an equivalent representation as a subset of formal mathematic logic referred to as predicate logic or first order logic. This observation extends to any system of objects and relationships such as Web Services, applications with a published API, or directories. In fact, much of the information contained in data sources across an enterprise infrastructure only makes sense in the context of the relationships between data objects. However, efforts to grasp the context of the data are hindered by the heterogeneity of diverse data sources, access protocols (SQL, LDAP, Web Services, APIs) with different data models and different implicit or explicit metadata buried inside different applications domains throughout the enterprise.
One attempt to bridge between diverse data sources relies on virtual directory technology. Virtual directory technology can abstract existing data sources such as databases, directories, and applications, and can integrate them into a common access layer. Any existing system of data sources can be represented by a model, i.e., a set of relationships between the core objects. By exploiting virtualization to build a common abstraction layer                for objects,        for the relationships between objects, and        the properties inside each object (as a set of binary relationships between the object identity and its attributes or properties),one can create a general global model of the data.        
What are needed are improved systems and methods for representing the context of data derived from diverse data sources.